Shots rang out at a Brooklyn community festival on Saturday evening, killing one person and wounding 11 others, officials said.
One of the victims was in critical condition and police said he was fighting for his life on Sunday.
No arrests have been made. Officials said there were two shooters and two guns.
The gunfire broke out just before 11 p.m. at the end of the Old Timers Day celebration, an annual community party featuring live music in Brownsville.
The party was wrapping up, but about a hundred police offers were still on the scene when the shots were fired at the Brownsville Playground along Hegeman Avenue and Sackman Street, police said.
Citizen App video shows police trying to clear a huge crowd to bring in stretchers.
A 38-year-old man died at the hospital. Seven of the victims were men and five were women, Police Commissioner James O'Neill said. The victims ranged in age from 21 to 55.
Police asked for anyone who was at the festival to share photos and videos from before, during and after the shooting.
"This tragedy does not define Brownsville," Mayor Bill de Blasio said at a press conference on Sunday. "It doesn't define the people of Brownsville."
He called for cooperation to get guns off the streets.
Public Advocate Jumaane Williams urged residents not to become complacent to gun violence.
"Every act of violence is a tragedy, each loss heartbreaking," he said. "We cannot become numb to that pain or to the incidents that cause it, we must meet each with strength, resolve, and action toward preventing the next."
The Old Timers celebration was originally held in 1963 to celebrate former members of the Brownsville Recreational Center who went on to achieve success in sports and other endavors, according to the New York City Parks website. It has become an annual event, sometimes spanning a week.